Fig. 7.

Effect of ROP on light/dark-stimulatory response. In the ROP 1 mg/L and 5 mg/L groups, the response was enhanced in the first, second, third, and fourth light condition compared to the CNTL (a, b); however, all light and dark conditions except sixth light were significantly different from HAL 10 mg/L (d, e). In the ROP 10 mg/L group, the response was significantly decreased in all dark conditions compared to the CNTL (c); however, the second and third light/dark conditions were significantly different from HAL 10 mg/L (f). CNTL: Control, HAL 10: Haloperidol 10 mg/L, ROP 1, 5, 10: Ropinirole 1, 5, 10 mg/L, ON: light-on period, OFF: light-off period. Tukey–Kramer test; *p <0.05, **p <0.01 from the CNTL vs the HAL 10 + ROP groups. All values are presented as means ± SEMs (n